Packet-based data networks are widely used to link various nodes, such as personal computers, servers, gateways, and so forth. Packet-based data networks include private networks, such as local area networks (LANs) and Wide Area Networks (WANs), and public networks, such as the Internet. The increased availability of such data networks has increased communication among nodes, whether the nodes are located in close proximity to each other (such as within an organization) or at far distances from each other. Popular forms of communications across such data networks include electronic mail, file transfer, network printing, web browsing, and other exchanges of digital data.
With the increased capacity and reliability of data networks, voice communications over both private and public data networks have become possible. Voice communications in a conventional public switch telephone network (PSTN) provides users with dedicated end-to-end circuit connections for the duration of each call. Unlike PSTN network, voice communications over data networks, such as IP (Internet Protocol) networks, has to compete the network bandwidth with other non-voice data (e.g. electronic mail, file transfer, web access, and other traffic). This makes the performance of voice data packets unpredictable if there is insufficient provision of quality of service.
In an IP network, each data packet is routed to a destination node based upon the destination IP address contained within the header of each packet. Each data packet may be routed over separate network paths before arriving at the final destination for processing. Transmission speeds of the various packets may vary widely depending on the conditions of the data paths over which the data packets are transferred. During peak usage of data networks, significant delays may be added to the transfer of voice data packets causing poor quality of voice communications. If there is insufficient provision of QoS in a congested network, voice data packets may be dropped in-transit to the destination due to inadequate or unavailable capacity of portions of data networks may result in gaps, silence, and clipping of audio at the receiving end.
A need thus exists for a method and system to improve the quality of voice calls or other audio communications over data networks.